Twenty-five years ago this month, Microsoft released an extension to its Disk Operating System (DOS) that gave users a graphical, mouse controlled environment with which to interface with their computers. Bundled with the new setup were a few applications like a drawing program, a simple word processor, an appointment calendar and a clock. Each program could be launched in its own box – or window – and tiled around the display screen. It wasn't a noted success but marked the start of a technology snowball that sees Windows currently being used on nearly 90 per cent of the world's computers.

Originally pegged for a future as something called Interface Manager, Microsoft's new graphical user interface for its MS-DOS operating system was renamed Windows ahead of a press launch in New York on November 10, 1983. Bill Gates announced that Windows 1.0 would be available by the following April. It was, in fact, a little late.

Not the first

Of course Windows wasn't the first, nor the only, graphical experience on offer to a growing number of computer users in the post-punk decade of the 1980s. The graphical user interface was born of research at XEROX PARC in the late 1970s. Apple's LISA computer offered a graphical Office System experience when it was introduced in January 1983.

The huge cost of VisiCorp's Visi On effort for IBM-compatible computers in December 1983 was likely the cause for its short life, while Apple's first Macintosh system brought a cheaper consumer option in January 1984. It was also faster than other solutions available at the time, was bundled with MacWrite and MacPaint and used familiar, real-world icons to represent virtual applications. Then GEM/1 brought some interface color to Atari ST computers in February 1985.

On November 20 1985, Windows version 1.0 was released. Bitmap displays and a mouse controlled cursor allowed users to open numerous boxes onscreen and click the mouse to start and run applications. In addition to an MS-DOS file management application and the MS-DOS Executive, users were treated to a calendar, a digitized card file system, a notepad, an onscreen clock and telecommunications programs. Instead of a one-at-a-time application environment, it was now possible "to work with several programs at the same time and easily switch between them without having to quit and restart individual applications."

The press release announcing Windows 1.0 explained that with multi-tasking, "it is easy to move from a spreadsheet program to a charting program, to a word processing program, and back to the spreadsheet program with a couple of keystrokes or click of a mouse. This greatly reduces the time normally required to switch from one application to another, allowing the user to interrupt an activity and return to it exactly where it was left off."

Windows 1.0 was not in fact a full operating system but rather a graphical front end for MS-DOS that offered icons instead of a command line prompt blinking on a blank screen and let users tile open windows or move them around like pieces in a jigsaw. Microsoft priced its new baby at US$99 and bundled in Paint and Windows Writer to sweeten the deal.

Onward and upwards...

Overlapping onscreen boxes only appeared with version 2.0 of Windows, released in December 1987. The new release was a vast improvement over the earlier outing and made the most of processing speed improvements offered by Intel's 286 processor, as well as increases in available memory. Users were given more onscreen control with navigational keyboard shortcuts, the Control Panel made its first appearance and non-Microsoft applications began to be written by third party developers.

Improvements continued with version 3.0 in May 1990. It offered more colors (16 of them), improved speed and was less buggy. Users were treated to improved icons, a file manager, print manager and program manager and better multi-tasking thanks to virtual memory. Third party developers were given a new Windows development kit that allowed them to concentrate on coming up with clever applications and worry less on creating drivers. Microsoft had success on its hands and as a result, this is probably the version that most PC users of a certain age are familiar with.

In April 1992 came Windows 3.1 that improved on the fonts, offered embedded objects, program reboots, and had screensavers for inactivity time-outs.

Launching a new version of Windows aimed at corporate users in 1993, Bill Gates said: "Windows NT represents nothing less than a fundamental change in the way that companies can address their business computing requirements." It was originally to be called Windows Advanced Server for LAN Manager but sensibly was renamed NT, which simply stands for "new technology" and, to keep it in line with other releases, had the number 3.1 added to the end.

Windows NT was a 32-bit system available in both workstation and server versions and was based on a brand new kernel. Amongst its many new features, it brought the now familiar NTFS file system and gave system analysts and mainframe programmers some graphical relief from all those eye-straining text-based interfaces that were still in widespread use at the time.

Also in 1993, Windows-based PCs became network aware for the first time with the introduction of Windows for Workgroups 3.11 – which also brought in features of particular interest to corporate users such as centralized configuration and security, significantly improved support for Novell NetWare networks, and remote access service (RAS).

And now for something completely different

The next year saw long file names being introduced to the business system (something youngsters may assume has always been possible) and the year after that brought with it something of a revolution. Before Windows 95, users would have to first install MS-DOS and then load Windows – very tiresome. DOS was still kicking around behind the scenes of course but its importance to system operation had given way to Windows. But the revolution didn't stop at DOS.

Windows 95 had a very different look and feel to everything that had gone before. Plug and play featured to ease hardware and software installation. A new taskbar and Start button and My Computer and the Recycle Bin appeared. It offered better support for multimedia, had built-in Internet capabilities via 32-bit TCP/IP (Transmission Control Protocol/Internet Protocol) and dial-up networking. Internet Explorer version 1.0 was also premiered. A million copies were sold within days of its release.

The Windows 95 user interface was introduced to the business platform with the unveiling of Windows NT 4.0 in 1996, which also added intranet management and development tools, the facility for higher network throughput and improved network support. The ability to close failed applications without rebooting the system no doubt helped to garner a reputation of stability and robustness for the new platform.

The next revision of Windows was made available in June 1998. The initial release caused a number of irritations – such as the shut down of a PC if it was left running for 50 consecutive days – and was quickly followed by a Second Edition the following year. The new flavor made getting connected to the Internet much simpler and once online, was much more dynamic thanks to the inclusion of IE5. It also included DVD read capability and support for the now ubiquitous USB. Windows Update helpfully informed users of available enhancements and patches for the first time and the MS-DOS kernel breathed its last breath.

A shaky start to the new Millennium

When it was discovered that the digital world didn't grind to a cataclysmic halt, Microsoft celebrated with a Millennium edition in September 2000. Although it brought many new and powerful features to the Windows environment, it was notoriously buggy and unstable. PC World magazine even went as far as renaming it "Windows Mistake Edition." However, automatic updates over the Internet, universal Plug and Play, System Restore, Windows Media Player 7 and Windows Movie Maker all made their debut.

The business world was also treated to Windows 2000 Professional which was designed to put NT 4.0, 95 and 98 to bed on corporate desktops and laptops.

Leaving behind the Windows 95 code base for good, Microsoft united business and consumer users with the release on Windows XP in October 2001. The user's visual experience was vastly improved over previous incarnations, Windows Messenger brought instant, real-time communication within reach and the much maligned but still widely used IE6 made an appearance. Various flavors emerged – including the Home and Professional editions, the excellent Media Center edition, the 64-bit edition and a tablet PC edition in 2002 – and by the end of 2006 it had sold over 400 million copies worldwide.

Microsoft took a long time to develop the next incarnation, codenamed Longhorn. The January 2007 release of Windows Vista caused a lot of initial excitement but, like Windows Me before it, was problematic enough to receive a good deal of derision. One of the main issues that caused ire amongst users was the number of alerts generated by the system's User Account Control. It could also be a little pedestrian in its operation.

However, it did introduce searching from the Start button and thumbnail previews and window transparency. Desktop gadgets/widgets or whatever you want to call them also made their first outing and despite its problems, Vista – in all its various editions – still managed to notch up considerable sales.

Windows today

And so (at last) to the latest version – which is of course Windows 7. Its October 2009 release brought support for touchscreen devices, easier home networking and a revamped, taller Taskbar – and a system tray which (thankfully) generates fewer pop-up alerts. Other features include one-click Wi-Fi that shows all the available networks and a much-improved Internet browser experience with IE8.

The Show Desktop icon from the Quicklaunch area of the taskbar of previous versions has been replaced with an Aero peek button that allows users to see through open windows to the desktop beneath. And installing the new operating system doesn't necessarily require a hardware upgrade, as previous versions inevitably had.

For some though, Windows 7 will always be associated with a certain thoroughly embarrassing promotional video:

This brief trip down memory lane has of course omitted much in the interests of brevity – such as the various corporate wranglings and legal challenges that have cropped up throughout the development of Windows, the other key platform developments such as Microsoft's DirectX multimedia technology and of course that productivity behemoth, Microsoft Office. We'll have to visit those another time...